If be: EC = 3:2, AB: EC = 4:1, then AE: AC: BC =?
Let EC = 2x, be = 3x, ab = 8x, BC = 5xae ^ 2 = AB ^ 2 + be ^ 2-2ab * becos ∠ B = 64x ^ 2 + 9x ^ 2-24x ^ 2 = 49x ^ 2ae = 7xac ^ 2 = AB ^ 2 + BC ^ 2-2ab * bccos ∠ B = 64x ^ 2 + 25X ^ 2-40x ^ 2 = 49x ^ 2Ac = 7 xAE:AC :BC=7x:7x:5x=7:7:5
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